Sweden is, or used to be, sort of like that. Sweden has high wealth inequality and more billionaires per capita than many other countries. But the whole thing is probably imploding now anyway.

I think people misunderstand a bit. It isn't wealth that is the problem as such. It is that wealth is a symptom of inequality. If you for example have good accessible schools for much of the population where having a privileged background doesn't matter much then naturally it will be relatively hard to get rich because there is so much competition.